The ability of a patient to self-deliver medication, e.g., in offsite therapy or where a nurse or caregiver is not immediately available, offers a solution to logistical issues arising from medical situations such as chronic therapy. Patient-controlled analgesia (PCA) is widely accepted in the field of pain management, as it enables patients to provide themselves with pain relief at times when such relief is most needed. PCA devices ideally include safeguards against overdoses and are easy and safe for a patient with little or no medical training to operate.
PCA devices often allow additional bolus doses of a predetermined amount of medication to be delivered to the patient, for instance when a patient needs or desires additional pain relief. After the bolus dose is delivered, the patient may continue to receive a normal (basal) rate of continuous infusion from an IV pump to which the PCA device is connected. In some cases, the basal rate is zero, meaning that the patient receives medication only when the PCA device is actuated.